The VR (Virtual Reality) technology adopts computer simulation to create a three-dimensional virtual world which provides users with simulations for senses of sight, hearing, touch and the like, as if they were personally on the scene. In the process of using the VR equipment, in order to relieve the sense of dizziness, it is necessary to reduce a delay effect of the image output. At the same time, in order to allow the eyes to capture a correct image, it is also necessary to reduce the time from the image output to the completion of an entire image display and a response time from the pixel point receiving a signal to the completion of the display. With the development of the optical technology and semiconductor technology, the OLED (Organic Light-emitting Diode) display has become a mainstream display device due to its advantages of high quality, small size, light weight, thin thickness, low voltage driving and low power consumption. Among them, the AMOLED (Active Matrix Driving OLED) has an extremely short response time and is applied to the VR equipment more and more often.
FIG. 1 is a schematic diagram of a structure of a conventional AMOLED display device, the pixel circuit and the timing sequence of which may be referred to FIG. 2 and FIG. 3. The conventional AMOLED display device at least includes a scan driver, a data driver, and a plurality of pixel units (P11, P12 . . . P21, P22 . . . Pn1, Pn2 . . . Pnm), and each pixel unit includes a plurality of TFT (Thin Film Transistor) switches (M1, M2 and M3) and a capacitor (Cst), and an OLED light-emitting device. Each of the pixel units is at least connected to a scan line (S1, S2, S3 . . . or Sn) and a data line (D1, D2, D3 . . . or Dn). The scan line Scan is used to provide an on or off signal for a TFT which controls writing of a data signal. The data line Data is used to cooperate with the timing sequence of the scan line Scan to write corresponding pixel information. In the AMOLED display device of FIG. 1, since the scanning signals are turned on line by line, the data signals, i.e., the pixel information, will be displayed instantly after being written into. Therefore, the motion blurring phenomenon will occur when a display frequency of an image cannot keep up with a changing frequency of the image, which results in poor user experience.
In order to alleviate the Motion Blurring phenomenon, as shown in FIG. 4 and FIG. 5, at least one light-emitting control signal line is introduced on the basis of the conventional AMOLED display device, and at least one TFT switch controlled by a light-emitting control signal En is added to a light-emitting path of its pixel circuit. The light-emitting control signals En of every pixel unit are connected together, and the light-emitting control signal En may be used to control the light-emitting time of the pixel. For example, as shown in FIG. 6, when the scan signals are turned on line by line, pixel circuits correspondingly write pixel data, i.e., the pixel information. At this time, the light-emitting control signal is turned off, and the display device does not display any content. Referring to FIG. 7, the vertical synchronization of the scanning process is controlled by a vertical synchronization signal Vsync, and the horizontal synchronization of the scanning process is controlled by a horizontal synchronization signal Hsync. When the output of the horizontal synchronization signal Hsync is completed, it indicates that writing of all the pixel information is completed. At this time, the sub-pixels in every rows of the display device are uniformly controlled through the light-emitting control signal En, to perform the light-emitting display according to the written data, so that the display device simultaneously displays the content of the image.
However, when the display device is large, the load of the light-emitting control signal is heavy due to the impedance of the line itself and the overlap between the lines. Besides, an instantaneous current of the light-emitting control signal is large at the moment of the level transition (As shown by the I-En waveform in FIG. 7). Based on this, when the OLED is applied to the VR equipment, the VR technology raises new requirements on the OLED display device, for example, how to generate the light-emitting control signal better.
It should be noted that the information disclosed in the above background section is only for the enhancement of understanding of the background of the present disclosure and therefore can include other information that does not form the prior art that is already known to one of ordinary skill in the art.